org.apache.xmlgraphics.image.loader.spi.ImageLoader Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/* $Id: ImageLoader.java 924666 2010-03-18 08:26:30Z jeremias $ */
package org.apache.xmlgraphics.image.loader.spi;
import java.io.IOException;
import java.util.Map;
import org.apache.xmlgraphics.image.loader.Image;
import org.apache.xmlgraphics.image.loader.ImageException;
import org.apache.xmlgraphics.image.loader.ImageFlavor;
import org.apache.xmlgraphics.image.loader.ImageInfo;
import org.apache.xmlgraphics.image.loader.ImageSessionContext;
/**
* This interface is implemented by classes which load images from a source. Normally, such a
* source will be an InputStream but can also be something else.
*/
public interface ImageLoader {
/** Used if the loading penalty is negligible (image doesn't need to be decoded). */
int NO_LOADING_PENALTY = 0;
/** Default/Medium conversion penalty (if there's some effort to load the image format) */
int MEDIUM_LOADING_PENALTY = 10;
/**
* Loads and returns an image.
* @param info the image info object indicating the image
* @param hints a Map of hints that can be used by implementations to customize the loading
* process (may be null).
* @param session the session context
* @return the fully loaded image
* @throws ImageException if an error occurs while loading the image
* @throws IOException if an I/O error occurs while loading the image
*/
Image loadImage(ImageInfo info, Map hints, ImageSessionContext session)
throws ImageException, IOException;
/**
* Loads and returns an image.
* @param info the image info object indicating the image
* @param session the session context
* @return the fully loaded image
* @throws ImageException if an error occurs while loading the image
* @throws IOException if an I/O error occurs while loading the image
*/
Image loadImage(ImageInfo info, ImageSessionContext session)
throws ImageException, IOException;
/**
* Returns the image flavor that is returned by this ImageLoader implementation.
* @return the target image flavor
*/
ImageFlavor getTargetFlavor();
/**
* Returns the penalty assigned to using this image loader. The value is used to select the
* best processing chain for images.
* @return the usage penalty (must be a non-negative integer)
*/
int getUsagePenalty();
}